Let me quote the MySQL 5.6 Replication article for both of these utilities:

mysqlfailover

“Provides continuous monitoring of the replication topology, enabling failover to a slave in the event of an outage on the master.

The default behavior is to promote the most up-to-date slave, based on the sets of GTIDs that have been applied, but the promotion policies are fully configurable. Therefore, a user can nominate a specific candidate slave to become the new master (i.e. because it is configured in a certain way or has better performing hardware), and the utility will automatically poll the other slaves to retrieve any events so far not replicated to the candidate slave’s relay log.

This ensures no replicated transactions are lost, even if the candidate is not the most current slave when failover is initiated.”

mysqlrpladmin

“If a user needs to take a master offline for scheduled maintenance, mysqlrpladmin can perform a switchover to a slave, defaulting to the most recent slave, or to a nominated candidate slave. It can also perform a manual failover in the event a master server has gone offline.

The utility can also be used to start and stop slaves, as well as provide slave discovery and basic monitoring, including

Status of the slave and its I/O and SQL threads;

Status of replication processing through the topology, including any lag or errors;

Configuration of slave promotion policies.

With either of these utilities, the user may register scripts to be called in the event of a slave promotion – for example to redirect an application to use the new master for writes and for reads that must always be consistent.”

The new MySQL Utilities are only included in MySQL Workbench, which you can download from: